1. Field of the Invention
The present invention relates to image processing, and in particular it relates to a method and apparatus for discriminating between a target and clutter in an image.
2. Background
The scenario in which this invention is applicable involves relative motion between target and clutter. Historically, clutter in imagery has caused great difficulty for segmentation processes that are used to differentiate between target and clutter. Clutter, at times, may appear to be very target-like.
There are many different state-of-the-art approaches to discriminate between a target and clutter in an image. One approach is to use a spatial filtering technique. Numerous different pattern recognition approaches may be used to discriminate between target and clutter. Statistical characterizations of the target and clutter have also been used in the discrimination process. There have been processes to increase the signal-to-noise ratio in imagery by integrating successive frames. This integrative process has been shown to work when objects in the image are moving. However, clutter which may obscure a moving target in an image containing both may have considerable body which doesn't appear to move in an image. It could, therefore, integrate up and produce a low target to clutter ratio, i.e. poor discrimination. The problem of integrating moving targets is solved by calculating and correcting for the velocity of the target before integrating. None of these approaches, however, address the problems that are addressed by this invention.